(1) Field of the Invention
The present invention relates to a device for the air dropping of platform mounted cargoes. Specifically, the present invention relates to a device utilizing a multi-staged parachute system which allows for a stabilized high speed descent of platform mounted cargo from aircraft operating at altitudes of up to 25,000 feet. Accordingly, some of the general objects of the present invention are to orient a load which is to descend by parachute in a low drag attitude and to maintain this attitude by limiting pitch oscillations to plus or minus 20.degree. in relation to the desired flight path trajectory.
(2) Description of the Prior Art
While on air drop missions, aircraft are vulnerable to surface-to-air missiles. To reduce this vulnerability, it has been shown that the air drop must be performed at higher altitudes than presently utilized. The desired range in altitude is up to 25,000 feet. When air dropping cargo from such high altitudes it is necessary to minimize wind drift error in order to assure that the cargo reaches the target area. In order to minimize the wind drift error, it becomes necessary to have the cargo traverse a greater portion of the trajectory path in a shorter period of time than is normally required for lower altitude air drops. This is accomplished by reducing drag and, as a result, increasing the rate of descent. However, the rate of descent must be appreciably reduced, before the cargo touches down, to be compatible with ground impact requirements.
A system designed for high altitude, high speed descent must also be provided with some means to stabilize the platform mounted cargo against pitch oscillations. It would also be desirable to provide a stabilized high speed descent device which could be utilized with conventional air drop aircraft.
Prior art platform mounted air drop devices are incapable of achieving stabilized high speed descent when used at high altitudes. While stabilized high speed descent systems for air dropping containers from high altitudes are known, these prior systems are not applicable to the air dropping of platform mounted cargo. This lack of applicability results from the fact that the dimensions and weight distribution of platform mounted cargo produces a high degree of instability when using systems designed for the air drop of containers.
Accordingly, the present invention has as some of its numerous objects the ability to increase the rate of descent during the initial stage of the drop of platform mounted cargo, to reduce wind drift and to reduce the rate of descent during the terminal stage of the drop of such cargo in order to meet ground impact requirements.